Allylsuccinic anhydride can be made by a Lewis Acid catalyzed ene reaction between maleic anhydride and propene according to reaction scheme 1 below: 
AlCl3 catalyzes the reaction efficiently but requires harsh conditions (T=200° C.). However, the anhydride undergoes exothermic polymerization at 205° C. For safety reasons, the industrial process should be performed 30° C. below the polymerization reaction. However, in these conditions, AlCl3 is not an efficient catalyst.
The ene reaction is the reaction of an alkene having an allylic hydrogen (ene) with a compound containing a double or triple bond (enophile) to form a new bond with migration of the ene double bond and 1,5-hydrogen shift.
Since the enophile, like the dienophile in a Diels-Alder reaction, should be electron deficient, complexation of Lewis acids to enophile containing basic groups promotes the ene reaction. See Snider, B. B. Acc. Chem. Res. 1980, 13, 426. The choice of the Lewis acid depends upon the enophile to be used. Some of them require very acidic Lewis acids, others require milder ones. Some examples of Lewis used for the ene reactions are: AlCl3, EtAlCl2, Me2AlCl, BF3, SnCl4, TiCl4, FeCl3, ZnCl2.
In the literature, the ene reaction between propene and maleic anhydride is described without catalyst but at a high temperature (200-250° C.). See (a) Alder, K.; Pasher, F.; Schmitz, A. Chem. Ber. 1943, 76, 27. (b) Phillips, D. D.; Hill, T. J. J. Am. Chem. Soc. 1958, 80, 3663. (c) Anderson, et al., 1966, U.S. Pat. No. 3,243,480.
U.S. Pat. No. 3,819,660 discloses the reaction of an alkene such as propene with maleic anhydride to produce an alkenyl succinic anhydride. That patent teaches the use of a mixture of para-toluene sulfonic acid and acetic anhydride as a catalyst.